1. Technical Field
Embodiments of the present disclosure are related to signal transmission, and more particularly to a signal relay device and a method for accessing an external memory via the signal relay device.
2. Description of Related Art
External memory systems, such as hard disks, floppy disks, optical disks, and others, allow permanent storage of large quantities of data. However, a central processing unit (CPU) can only directly access data that is in main memory. To process data in an external memory, the CPU must first transfer the data to the main memory. An external memory controller is often used for completing the data transfer between the external memory and the main memory. However, the external memory controller can only send one command, that is, one read or write command, to the external memory at one time, with the subsequent command waiting for completion of the current command. As a result, considerable time is spent on the data transfer when numerous commands are required, and bandwidth of the external memory is not fully utilized.